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Accueil du site → Doctorat → Israel → Evaluation of spatial and temporal variations of thermal-water stress of dry land forest from satellite images

Ben-Gurion University of the Negev (2009)

Evaluation of spatial and temporal variations of thermal-water stress of dry land forest from satellite images

Sprintsin, Michael

Titre : Evaluation of spatial and temporal variations of thermal-water stress of dry land forest from satellite images

Auteur : Sprintsin, Michael

Université de soutenance : Ben-Gurion University of the Negev

Grade : Doctor of Philosophy (Ph. D.) 2009

Descriptif
Knowledge of the eco-physiological processes affecting the functioning of forest ecosystem is essential for understanding responses of terrestrial vegetation to climate changes. These changes have an impact on biosphere productivity due to an increase in the frequency of droughts events that reduce water availability. Although the latter is an important factor responsible for forest growth, its potential interaction with other stand variables frequently ignored by studies conducted in semi-arid environments. With this work it’s presented an integrated approach that evaluates the functioning of the dryland planted coniferous (Aleppo Pine) forest located in a southern Israel (31˚21’ N and 35˚02’ E). The objective of this study was to determine and to analyze forest biophysical parameters, their spatial dynamics and interactions with environmental variables in order to assess the spatial and temporal variation of forests’ water consumption at the edge of dry spell (Table 1) using multi-spectral satellite observations. This study investigates and discusses the major aspects of this topic and explores the relationship between the large-scale heterogeneity in forests’ vegetation cover and the exchange of mass and energy across the surface boundary layer (Fig.1). The work has summarized two years of (a) standard forest inventory performed over the seventy-two circular plots (200 m2 each) located in the most mature ( 39-year-old) section of a forest ; (b) leaf area index (LAI) estimations (by means of Tracing Radiation and Architecture of Canopies photo-sensor device) over ten (∼1000 m2) plots and (c) transpiration measurements performed by thermal dissipation and heat pulse methods. Analyzed datasets were obtained from (1) multispectral IKONOS imagery ; (2) LAI/FPAR and surface reflectance standard operational products of MODIS ; (3) optical and thermal ASTER images. Canopy scale measurements of water vapor, energy exchange and general meteorological data were observed directly by micrometeorological tower (IL-Yat site of CarboEurope network).

Mots Clés  : Arid regions plants — Remote sensing. — Arid soils — Israel — Remote sensing. — Forest microclimatology. — Forests and forestry — Israel. — Plant-water relationships. — Plants — Effect of drought on. — Bet Yatir.

Annonce (BGU)

Page publiée le 9 janvier 2012, mise à jour le 21 novembre 2018